Is 8K Necessary?

SMPTE recommends the ideal distance from the movie screen to be subtended by a viewing angle of 36 degrees. Any closer and the outer edge of the screen is outside easy peripheral viewing. The acuity of the human eye is limited by the finite number of rods and cones for a resolution of one minute of arc. At 60 minutes of arc per degree times 36 degrees that makes the finest useful resolution 2160 pixels wide, which closely matches that of 4K. The human eye will see no sharper an image at 8K, so why waste money on going from 4K to 8K?

Barney Vincelette / Houston, DE

AG responds: You make a solid argument for the primacy of 4K, and the excessive nature of 8K when it comes to home viewing. I’m guessing your letter was prompted by our review of JVC’S 8K- capable DLA- NZ9 projector in the February/ March issue. We, too, were uncertain about the benefits, but to quote from Kris Deering’s review: “Where I do see the benefit is when any type of image processing such as scaling and enhancement is being applied. With 8K, these extra processes extend over far more pixels and as a result lack the immediate artifacts you may see at lower resolutions, 4K included. Viewing in 8K also helped with motion resolution.” Kris further stated, “I also noted a subtle increase in apparent depth, dimension, and detail on lots of material I regularly use for testing. So, while I was quite the skeptic about viewing standard HD and 4K content on an 8K display going into this review, the more I watched the more I liked it.”